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NetLab Interactive network lab

Interactive Network Lab

Explore packet flow, routing decisions, firewall rules and protocol behaviour directly in the browser.

JavaScript enables the interactive simulation. The fallback content below keeps the lab understandable for crawlers and browsers without script execution.

Packet path simulator

Check whether a destination is local, routed through a gateway, or blocked by invalid addressing.

Packet steps

    Routing decision lab

    Test longest-prefix matching and gateway selection with a small editable routing table.

    Routing table
    Test destination

    Routing result

    Hint

    More specific prefixes win over broader routes. A default route catches everything else.

    Firewall rule lab

    Evaluate a packet against ordered allow/deny rules and see which rule matches first.

    Firewall rules
    Packet to test

    Firewall result

    Hint

    Firewall rules are evaluated in order. The first matching rule decides the result.